Respirometer



Dec. 30, 1969 w. E. GlLsoN 3,486,983

' RESPIROMETER Original Filedr March 2'7, 1964 4 Sheets-Sheet 1 N m wfg M m, xm i# Dec. 3o, 1969 y w, Ef GLSON 3,422.6,983v

RESPIROMETER Original Filed March 27, 1964 4 Sheets-Sheet 2 y WWI @www HU Dec. 30, 1969 w. E. GlLsoN 3,486,983

RESPIROMETER Original Filed March 27, 1964 4 Sheets-Sheet 5 I ff/52 /68 rroeA/Eys.

Dec. 30, 1969 w E, GlLsON 3,486,983

RESPIROMETER Original lFiled March 2'7, 1964 4 Sheets-Sheet 4 AWWA/sys.

United States Patent O 3,486,983 RESPIROMETER Warren E. Gilson, Madison, Wis., assignor to Gilson Medical Electronics, Inc., Middleton, Wis., a corporation of Wisconsin Original application Mar. 27, 1964, Ser. No. 355,158, now Patent No. 3,313,157, dated Apr. 11, 1967. Divided and this application Nov. 3, 1966, Ser. No. 607,092

Int. Cl. B011 3/00; C12b 1/22 U.S. Cl. 195-127 6 Claims ABSTRACT OF THE DISCLOSURE A differential -respirometer system includes a single reference flask and several active flasks all connected to a common manifold, together with a differential manometer for each active flask and an arrangement of valve's for disconnecting `the active flasks from the manifold and for controlling the manometers. The flasks are supported on slides movable on supports into and out of a liquid ybath container, the slides including manually movable detent arms for holding the slides on the supports. Additional supports in front of the container can hold the slides in a ready position. The flasks may be shaken by oscillating the support for the slides.

This application is a division of the copending application of Warren E. Gilson, Ser. No. 355,158, filed Mar. 27, 1964 now U.S. Pat. No. 3,313,157.

The present invention relates to improvements in respirometers and has for its primary object the provision of a new and improved flask supporting assembly.

An object of the invention is the provision of a new and improved respirometer comprising a novel flask support and means movably supporting the former in different positions within and outside a container.

In brief, the differential respirometer and system includes a container adapted to contain a liquid bath in to which both active and reference flasks may be placed. In accordance with the present invention, the flasks are constructed as slidable sub-assemblies and carriers for the slides are provided inside of and at the front of the container. The slides and carriers are so constructed that the flasks may 'be located at high and low positions on the carriers both inside and outside of the container. The slides are all mounted on a shaker mechanism so that the flasks may be shaken during the experiment.

Other objects and advantages of the present invention will lbecome apparent from the ensuing description of an illustrative embodiment in the course of which reference is had to the accompanying drawings, in which:

FIG. 1 is a diagrammatic representation of a differential respirometer system constructed in accordance with the present invention; i

FIG. 2 is a fragmentary and partly broken away front view of the differential respirometer;

FIG. 3 is an enlarged fragmentary vertical cross sectional view taken along the line 3-3 of FIG. 2 illustrating the manometer with its associated valves in their closed positions;

FIG. 4 is a further enlarged fragmentary View taken along the line 4-4 of FIG. 2 and illustrating additional details of a manometer;

FIG. 5 is a vertical cross sectional view taken along the line 5-5 of FIG. 4 and illustrating details of construction of a valve;

FIG. 6 is a fragmentary elevational view taken along the line 6-6 of FIG. 4 and illustrating a movable cursor forming part of a manometer;

FIG. 7 is an exploded View illustrating details of construction of the valves embodied in the apparatus;

ice

FIG. 8 is a fragmentary vertical cross sectional view taken along the line 8 8 of FIG. 2, illustrating in solid lines a flask and `associated support with the flask immersed in the bath and illustrating in phantom the flask in aposition corresponding to the first but elevated above the 'container and illustrating in a further phantom p0- sition the flask support in front of the apparatus;

FIG. 9 is a horizontal cross sectional view taken along the broken line 9 9 of FIG. 8; and

FIG. l0 is a similar view taken along the line 10-10 of FIG. 8.

Referring now to the drawings and first to FIG. 1, the'system of the present invention is there shown quite diagrammatically. The system, indicated as a whole by reference character 10, includes a plurality of active flasks 12.-and a single reference flask 14 all supported in a liquid bath 16 below the level of the liquid which is indicated Aby reference character 18. The reference flask 14 is connected, as by flexible tubing 19, to a mani-fold 20 provided with a valve 22 at its end whereby the manifold.. may be connected to atmosphere or evacuating means, or a source of gas, not shown, through a conduit 24.

The system includes also a plurality of differential manometers 30 all of identical construction and only one of which will be described. Each manometer includes two legs 32 and 34 of which the latter is connected to an active flask through conduit 36 which may be of or include flexible tubing or the like and a combined tube and stopper 38. The interconnected lower ends of the arms 32 and 34 are provided with manometer fluid 40 and the legs are provided with index marks 36 (only one leg may have associated with it such a mark on a movable cursor, as will be described in greater detail hereinafter).

A shut off valve 42 of a novel construction, to be described hereinafter, is provided between the two legs of the manometer at the level of the end of tube 36 leading to manometer leg 34. This valve may be opened or closed and performs the two functions necessary for an experiment which requires gassing. The functions are: (l) to provide a connection between the two legs of the manometer to equalize pressure and (2) momentarily to connect the flask side of the manometer to atmosphere for pressure equilibration. Generally the valve is closed. The upper end of manometer leg 32 is provided with a shut off valve 44, which is like the valve 42, for the purpose of enabling individual disconnection of the manometer from the manifold 20. The upper end of manometer leg 32 lbeyond the valve 44 is connected to the manifold as by a short piece of tubing 46.

Considerable simplification in use of the equipment is provided by a volumetric micrometer 50 at the upper leg of arm 34 which is utilized to return the manometer fluid to a balanced condition by movement of a piston in the enclosed volume. 'Ihe micrometer is calibrated to read directly in microliters thereby considerably simplifying calculations.

In Ioperation of the system of FIG. 1, all the valves 44 are opened. These valves are generally left open all the time and are seldom used. Actually they are used only to disconnect a flask-manometer combination if it is not to be used in an experiment. The valve 22 likewise is open to connect the manifold to atmosphere or to some other gas should such be used. The valves 42 are also open. The reference flask 14 contains the same solution, usually plain water, as is used in the active flasks 12. A respiring material to be tested is placed in the active flasks and during a test this material generally consumes oxygen from the air. The micrometer 50 is adjusted to some convenient reading, say 200 microliters.

In performance of a test, all the valves 42 are closed and as will be described hereinafter this is accomplished advantageously by means of a single valve operating handle. During the test the respiring material absorbs the oxygen with the result that the liquid in the leg 34 connected to the active flask rises and that in the other leg lfalls. During the experiment readings are obtained at suitable time intervals by operating the micrometer 50 to bring the liquid in the manometer legs into balance. The readings are direct readings in microliters so that the readings are obtained simply and quickly.

The advantages of the system are freedom from varying barometric pressures or changing temperatures in the water bath. The manometers and volumetric micrometers are also visible at all times. Also, great convenience Ais alforded in changing the gases that may be used and other advantages result from the equipment to be described.

The detailed construction of the apparatus will now be described. In this description the reference characters utilized in FIG. 1 will be applied to the apparatus as far as possible. Parts of the apparatus not important tothe present invention have not :been illustrated in detail.

Referring rst to FIGS. 2 and 8, the apparatus includes a base 60 shown only fragmentarily. Supported on the base is a container 62 for the liquid bath 16, which is shown rising to a level 18 and in which the asks are immersed in use. Two of the flasks are shown in FIG. 2. For purposes of description it will be assumed that the flask shown at the left in FIG. 2 is an active ask 12 and the one shown at the center is the reference flask 14. These flasks are shown supported within the container 62 and they would be immersed in the bath, which is generally maintained at a predetermined temperature.

The liasks are supported on a mechanism adapted continuously to be oscillated thereby to shake the asks with their contents. This mechanism is indicated by the reference character 64 and it comprises a cross arm 66 extending over the top of the container 62 and a pair of upstanding arms 68 at the opposite ends of and outside of the container. The arms 68 are pivotally mounted and pivotally related to the cross bar 64. Also, they may be oscillated by a motor or the like in a manner not shown.

In the illustrated embodiment provision is made for a reference flask and four active flasks. The individual asks are detachably mounted on downwardly extending channel type supports or carriers 70 constituting vertically disposed slideways with detent apertures 72 and 74 utilized in holding the flask assemblies in the bath or removed from and above the bath. The supports 70 are secured at their upper ends to the cross arm 66 as by screws 76.

The flask assemblies are best illustrated in FIGS. 8, 9 and 10. A ask assembly includes a channel type slide 80 nested and slidably received in the supports 70 so that the slide 80 may readily be moved up and down in and removed from the supports 70. The slide 80 is adapted to be held in two positions on the carrier 70 Vby an elongated and generally triangularly shaped latch or detent arm 82 having a short detent nger `84 at its lower end. In the solid line position illustrated in FIG. 8, the detent finger 84 is located in the lower aperture 72 thereby holding the slide 80 in its lower position with the flask 14 immersed in the liquid bath 16. In the `dotted line position, the ask 14 is lifted above the container 62, thereby making the flask easily available for inspection or change, etc. In this upper position the detent finger 84 projects into the aperture 74.

The detent arm 82 is pivotally supported on the slide by a pivot bolt 86 passing through a bushing 88 and a pair of opposed tube supporting brackets 90 having arcuate end portions 92 encircling the combined tube and stopper 38. The upper vertical part of member 38 is releasably secured in the brackets 90, being releasable upon loosening of the screw bolt 94. Member 38 has a horizontal portion 38A that is held between opposed arcuate bracket portions 92A, the better to hold it in oriented position. As illustrated, the ilask is held in assembled relation relative to the tube and stopper by a pair of springs 96. The springs are releasable from both the flask and the tube so that the flask may be readily detached as desired.

The `detent arm 82 is biased into position to engage the bottom of the carrier 70 so that the detent finger 84 will readily slide into either aperture 72 or 74 as the slide iS moved in the carrier. This biasing is effected by a leaf spring 98 secured to the forward part of arm 82 and having a rounded portion 98A engaging the slide. The slide is provided with an upstanding bent finger 100 and the detent arm with a forwardly bent finger 102 at the level of the finger so that the detent may be easily operated to release the assembly.

The horizontal portion 38A of the combined tube and stopper 38 is adapted to be connected by a length of flexible tubing corresponding to tubing 36 of a length Suficient to enable the flask assembly to be moved to the upper phantom position and, in accordance with another feature of the invention, to a position in front of the container 62, where it can be supported on a carrier 70A in all respects like the carrier 74 but secured to the front of the cabinet upon a crosspiece 104. Accordingly, the flask assembly can be secured at the front of the cabinet in either a low or high position depending on whether or not the detent finger 84 is in the upper aperture 74A or the lower one 72A.

The manometers 30 and volumetric micrometers 50 are supported above and to the rear of the container 62 upon a pair of spaced apart uprights suitably secured to the base 60. The spaced supports are interconnected at their upper rear ends -by a crosspiece 112 forming also a support for the micrometers, the latter being secured thereto by screws 114, see particularly FIGS. 2 and 3. The end supports 110 are additionally interconnected by a lower crosspiece 116 and an intermediate one 118 which is also spaced back from the former and which provide a two point support for the manometers, the latter being secured thereto by the screws 120 and 122, see particularly FIG. 3.

A pair of rods 124 and 126 also extend between the spaced uprights 110. These are utilized for guidance of the exible tubing 36 heretofore referred to as connecting the asks to the manometers which tubing may be maintained taut by suitable tube retracting mechanism, not shown. A series of spools 128, only one of which is shown, may be placed on the rods for guidance of the tubing.

The volumetric micrometer 50 includes a body 130 and a rotatable and axially movable adjusting element 132 to the lower end of which is attached a piston 134, see FIG. 4, adjustable closing the upper end of the manometer leg 34 which is connected by the tubing 36 to the reference ask. The micrometer 50 is constructed and arranged to provide digital readings directly in microliters in a range from 0 to 500. The digital reading for 200 microliters is illustrated on the micrometer on the extreme left of FIG. 2, the digits being on the three rotating discs 136.

The micrometer is detachably secured to the upper end of manometer leg 34 by a coupling element 138. Referring to FIG. 4 the coupling engages a split bushing 140 at its lower end and, likewise, engages a sealing washer 142 between the body and upper end of manometer leg 34. An O-ring 144 is provided to provide sealing around the piston 134.

The manifold 20, which has a longitudinal passageway 20A therein, is also supported by the manometers between the crosspieces 110, as by short pieces of flexible tubing 146. One end of the manifold may also be supported in a manner not shown by one of the uprights 110 and this end may have attached to it the valve 22 referred to in connection with FIG. 1.

A movable cursor 150, illustrated in FIGS. 4 and 6, is slidably mounted between the manometer legs 32 and 34. It is of telescopic construction including an outer portion 152 and an inner portion 154 that are biased apart by a spring 156 so that the outer ends of the portions movably abut against the legs 32 and 34. The portion 154 is provided with an index line 158 which is normally at a point at which the height of the liquid in both legs is the same and which can be seen through the transparent material of which the manometer is made.

The valves 42 and 44 are the same in construction and only one will 'be described while like parts are indicated by like reference characters. e

Each valve includes a body 160 having a transverse recess 162 rotatably receiving a cylindrical plug valve element 164 having a transverse passageway 166 through it. Referring particularly to FIGS. 5 and 7, it will be noted that the 'body is provided with counterbores 168 at its opposite ends for the reception of O-rings 170 providing sealing around the plug. One of the O-rings is held in compression by a collar 172 secured to a projecting end of the plug as by a set screw 174. The opposite end of the plug is held in assembled relation by the valve operating handle or rod 176 between which and the body there is located a washer 178. The handle is movable from its solid line closed position, determined by stop 177A, to a dotted line open position, determined by stop 177B. The pasageways in the valve body leading to the plug at the interior of the valve are provided with counterbores 180 of arcuate nature to receive O-rings 182 and to confine them in arcuate relationship to the exterior of the valve body thereby to seal the passageways controlled by the valve body.

The manometers are all supported in a horizontal line and so as to be visible at all times. Also, in accordance with the present invention, the valves 42 controlling communication between the legs of the manometer are arranged and constructed so as to be openable or closable simultaneously as well as individually. These valves are each provided -with a somewhat elongated handle 184 by means of which the valves may be individually operated. LReferring to FIG. 3, the handle 184 is shown in solid line in the position it occupies when the valve is closed while the open position is shown in phantom.

Simultaneous movement of all of the valves to their dotted line open positions can be effected by movement of a handle operator indicated as a whole by the reference character 186. The latter is mounted at the outer ends of arms 187 secured to a rotatable shaft 188, the opposite ends of which are received in the end supports 110. The outer ends of lever 187 of the handle operator are connected by a transverse rod 190 which is engageable with all of the handles 184. Consequently, when the operator 186 is moved from its solid line to its dotted line position, as shown in FIG. 3, the valve is opened. The closed position of a valve is determined by a stop 192 and the open position by a stop 194. To facilitate movement of operator 186 there are provided a pair of forwardly extending operating levers 196 which are secured to the levers 187. It should be noted that the levers 196 are located, as are the levers 187, at the inner sides of the support 110.

Simultaneous movement of the valves 42 from their dotted line open position to the solid line closed position is effected by a second handle operator 198. It includes a transverse rod 200 mounted at the free ends of levers 202 mounted on a rotatable cross shaft 204 mounted upon the supports 110. -Operating levers 206 are attached to the levers 202 so that the operator may readily manipulate the handle operator. These levers are mounted at the outer sides of the end supports 110.

Both handle operators 186 and 198 are biased to their indicated upper positions lby springs. The spring for operator 186 is indicated by reference character 208 and that for operator 198 by 210. The up position of handle 184 is determined by opposed stop pins 212 projecting a short distance inwardly from each end support 110.

The manometers and the volumetric micrometers are preferably made by injection molding of some suitable plastic material, such as Lexan. Accordingly, they may be made and assembled quite readily in an apparatus such as shown.

The use of the system as a whole has already lbeen described. A brief review will now be made of the use of the specically described construction of the apparatus. At the start of an experiment the ask slides are moved into their upper positions above the container 62 or to the front of the container, as illustrated in FIG. 8. Thereafter the material to be placed under test is placed into the active flasks 12 and the reference ask is `supplied with a solution corresponding to that used in that of the active flasks. It may be noted that the flasks are easily detached from or mounted upon the combined tubes and Stoppers 38 mounted upon the slides 80. To place the slides and asks in the liquid bath in the container, the finger pieces and 102 may be grasped thereby to operate the detent arm 82 to release the detent 84, for example from the aperture 74. Thereafter the slides 80 may be lowered in the carrier 70 until the latch 84 goes into the aperture 72, which it does under the inuence of leaf spring 78. As previously indicated, the shut of valves 44 are normally open. In order to balance the pressures in the manometer legs the valves 42 are all opened by movement of handle operator 186 by means of its lever 196. This at the same time not only balances the pressures in the manometer legs but also equalizes the pressures in the system as a result of connection thereof to the manifold, which is open to atmosphere, or some other gas or pressure source.

Thereafter the valves 42 are all closed by operation of handle operator 198 through its operating lever 206.

Assuming that the micrometer had been set at 200 microliters to provide equal heights of liquid in manometer legs 32 and 34, then during the experiment readings may be taken by adjustment of the micrometer to bring the level of the liquid in the manometer legs back to the same height, which may be readily determined by use of the cursor and its index 158. As previously indicated, the micrometer is calibrated in microliters so that the readings can be taken quickly and simply.

After the experiment is over the flask assemblies and carriers 80 may be lifted to a position above the container or, if desired, they may be removed entirely from within the container and attached to the supports 70A in front of the container.

While the present invention has been described in connection with details of an illustrative embodiment thereof it should be understood that such details are not intended to be limitative of the invention except insofar as set forth in the accompanying claims.

What is claimed as new and desired to be secured by Letters Patent of the United States is:

1. A ask holding assembly for use with a container and comprising in combination, a plurality of elongated generally vertically disposed supports extending upwardly from the container, a plurality of slide members each adapted slidably to be mounted on a support for generally vertical sliding movement thereon, a ilask holding means on each slide member, a pair of first detent means located at upper and lower locations on each support, a detent arm pivotally mounted on each slide member and including a second detent means engageable with one of said upper and lower first detent means for holding the slide member in upper or lower positions on the support thereby to hold a flask within or above said container, spring means biasing said detent arm to a position in which said second detent means engages said rst detent means, and a manually movable portion of said detent arm disposed at the upper portion of said slide member for pivoting said detent arm against the force of said spring to disengage said second detent means from said first detent means to release the slide member.

2. The assembly of claim 1 further comprising further supports mounted in front of said container adapted slidably to support said slide members.

3. The assembly of claim 1, a single supporting means supporting all of said supports, and means for oscillating said single supporting means to shake the flasks.

4. A container, channel type supports mounted at the upper side of and extending down into the container, other channel type supports mounted in front of and outside the container, channel type slides adapted movably to nest on the supports, ask supporting means on each slide, means including detent means movably mounted on each slide for holding the slide in position on the support wherein it is located in the container and removable therefrom to be supported on the supports in front of the container.

5. A container, channel type supports mounted at the upper side of and extending down into the container, channel type slides movably nested on the supports, flask supporting means on each slide, and detent means movably mounted on each slide for holding the slide in a rst position on the support wherein it is located in the container and a second position wherein it is above the container, other channel type supports mounted at the front of and outside the container, said slides being removable from the support in the container for attachment on the slides at the front of the container.

6. A ask holding assembly including a channel support, a channel slide movably nested on the support, flask supporting means on the slide and a detent arm pivotally mounted on the slide intermediate the ends of the arm and having a rst portion extending to near the bottom of the slide and a second portion extending above and forward of the slide terminating in a finger piece, spring means between the arm and slide biasing the lower end of the arm toward the slide, the slide also having a projecting linger piece at the level of the rst mentioned finger piece, whereby the two nger pieces may be readily grasped to manipulate the detent arm, the rst portion of the arm having a detent nger projecting through the slide, and said support having apertures near its upper and lower ends into which said finger projects to hold said slide in high or low positions on the support.

References Cited UNITED STATES PATENTS 1,449,744 3/1923 Caldwell 18-24 1,890,939 12/1932 Fahrney 23-259 1,946,360 2/1934 Roberts 18-24 2,389,319 11/1945 McMordie et al. 18-24 2,437,109 3/1948 Maquat 18-24 3,026,187 3/1962 Robertson 23-292 MORRIS O. WOLK, Primary Examiner R. E. SERWIN, Assistant Examiner U.S. Cl. X.R. 

